Project description:MicroRNAs (miRNAs) are small noncoding RNAs that participate in regulation of gene expression. Their role during mammary gland development is still largely unknown. In the present study, we performed a microarray analysis to identify miRNAs associated with high mammogenic potential of bovine mammary gland. We identified 54 miRNAs differing significantly between mammary tissue of dairy (Holstein-Friesian, HF) and beef (Limousine, LM) post-pubertal heifers. Fifty two miRNAs had higher expression in the mammary tissue of LM heifers. Enrichment analyses for targeted genes revealed that the major differences between miRNA expression in the mammary gland of HF vs. LM were associated with regulation of signalling pathways crucial for mammary gland development, such as: TGF-beta, insulin, WNT and inflammatory pathways. Moreover, a number of genes potentially targeted by differentially expressed miRNAs was associated with mammary stem cells’ activity. These data indicate that in dairy cattle high developmental potential of the mammary gland, leading to high milk productivity, not only depends on central neuro-endocrine regulation but also on specific miRNA expression pattern. miRNA profiling of Holstein Freisian (dairy breed) and Limousne heifers (beef breed) mammay glands. Two-condition experiment, LM (test) vs. HF (reference). Total RNA was isolated from quarters of 4 LM and 4 HFmammary glands.
Project description:Bovine mammary stem cells (MaSC) are a source of ductal and lobulo-alveolar tissue during development of mammary gland and its remodeling in repeating lactation cycles. We hypothesize that the number of MaSC, their molecular properties and interactions with their niche may be essential to determine the mammogenic potential in heifers. To verify this hypothesis we compared the number of MaSC and transcriptomic profile in mammary tissue of 2-year-old, non-pregnant dairy (Holstein-Friesian) and beef (Limousin) heifers. For identification and quantification of putative stem/progenitor cells in mammary tissue sections scanning cytometry was used with a new combination of MaSC molecular markers: stem cell antigen-1 (Sca-1) and fibronectin type III domain containing 3B (FNDC3B) protein. Double labeled cells were located mainly in the basal layers of mammary epithelium. Cytometric analysis of Sca-1pos FNDC3Bpos cells revealed significantly higher number in HF (2.94M-BM-10.35%) than in LM (1.72M-BM-10.20%) heifers. More advanced development of mammary tissue in HF heifers was accompanied by higher expression of intramammary hormones, growth factors, cytokines, chemokines and transcription regulators. The model of transcriptomic niche favorable for MaSC was associated with regulation of genes involved in MaSC maintanence, self renewal, proliferation, migration, differentiation, mammary tissue remodeling, angiogenesis, regulation of adipocyte differentiation, lipid metabolism and steroid and insulin signaling. In conclusion the high mammogenic potential in postpubertal dairy heifers is facilitated by a higher number of MaSC and up-regulation of mammary auto-, paracrine factors representing MaSC niche. Keywords: stem/progenitor cells, transcriptomics, mammary gland, dairy and beef heifers Two-condition experiment, LIM vs. HF. Pulled quarters of mammary glands form 10 LIM heifers (test) and 10 HF heifers (reference). Sample 3 and 4 are dye swaps.
Project description:Bovine mammary stem cells (MaSC) are a source of ductal and lobulo-alveolar tissue during development of mammary gland and its remodeling in repeating lactation cycles. We hypothesize that the number of MaSC, their molecular properties and interactions with their niche may be essential to determine the mammogenic potential in heifers. To verify this hypothesis we compared the number of MaSC and transcriptomic profile in mammary tissue of 2-year-old, non-pregnant dairy (Holstein-Friesian) and beef (Limousin) heifers. For identification and quantification of putative stem/progenitor cells in mammary tissue sections scanning cytometry was used with a new combination of MaSC molecular markers: stem cell antigen-1 (Sca-1) and fibronectin type III domain containing 3B (FNDC3B) protein. Double labeled cells were located mainly in the basal layers of mammary epithelium. Cytometric analysis of Sca-1pos FNDC3Bpos cells revealed significantly higher number in HF (2.94±0.35%) than in LM (1.72±0.20%) heifers. More advanced development of mammary tissue in HF heifers was accompanied by higher expression of intramammary hormones, growth factors, cytokines, chemokines and transcription regulators. The model of transcriptomic niche favorable for MaSC was associated with regulation of genes involved in MaSC maintanence, self renewal, proliferation, migration, differentiation, mammary tissue remodeling, angiogenesis, regulation of adipocyte differentiation, lipid metabolism and steroid and insulin signaling. In conclusion the high mammogenic potential in postpubertal dairy heifers is facilitated by a higher number of MaSC and up-regulation of mammary auto-, paracrine factors representing MaSC niche. Keywords: stem/progenitor cells, transcriptomics, mammary gland, dairy and beef heifers
Project description:MicroRNAs (miRNAs) are small noncoding RNAs that participate in regulation of gene expression. Their role during mammary gland development is still largely unknown. In the present study, we performed a microarray analysis to identify miRNAs associated with high mammogenic potential of bovine mammary gland. We identified 54 miRNAs differing significantly between mammary tissue of dairy (Holstein-Friesian, HF) and beef (Limousine, LM) post-pubertal heifers. Fifty two miRNAs had higher expression in the mammary tissue of LM heifers. Enrichment analyses for targeted genes revealed that the major differences between miRNA expression in the mammary gland of HF vs. LM were associated with regulation of signalling pathways crucial for mammary gland development, such as: TGF-beta, insulin, WNT and inflammatory pathways. Moreover, a number of genes potentially targeted by differentially expressed miRNAs was associated with mammary stem cells’ activity. These data indicate that in dairy cattle high developmental potential of the mammary gland, leading to high milk productivity, not only depends on central neuro-endocrine regulation but also on specific miRNA expression pattern.
Project description:The liver of dairy cows naturally displays a series of metabolic adaptation during the periparturient period in response to the increasing nutrient requirement of lactation. The hepatic adaptation is partly regulated by insulin resistance and it is affected by the prepartal energy intake level of cows. We aimed to investigate the metabolic changes in the liver of dairy cows during the periparturient at gene expression level and to study the effect of prepartal energy level on the metabolic adaptation at gene expression level.B13:N13